Grille and method of making the same



Jan. 24, 1939.. G. F. DRAKE GRILLE AND METHOD OF MAKING THE SAME 2 Sheets-Sheet 1 Filed Dec. 19, 1936 paw dad ca QwadZF 2% MM D Lo .4. Y Re or R m 0 EF U V .IA mwu m r a P e m Jan. 24,1939. F. DRAK'E 2,1 5,0

GRILLE AND METHOb MAKING THE SAME Filed Dec. 19, 1936 2 Sheets-Sheet 2 INVENTOR George Forres If .Dra/rc BY MIM ATTORNEYS I Patented Jan. 24, 1939- PATENT orrlcs can: .mn'ms'rnon OF'MAKING THE SAME I 1 George Forrest Drake, Rockford, IlL, assignonby mesne assignments, to Barber-Colman Company, Rockford, 111., a corporation of Illinois Application December 19, 1936. serial No. 116,688

4 Claims.

This invention relates to grilles for coverin the open ends of air ducts and the like and has more particularreference to the construction of the so-called core of the grille.

The primary object f the invention is. to provide a novel grille construction which may be formed by perforating and folding a single sheet of metal and which has fins of any desired width and lateral spacing, each comprising a single thickness of the metal sheet,

A more detailed object is to provide a folded sheet metal grille core of the above character having its fins held in spaced relation by connecting elements integrally joined at opposite ends to opposite sides of the adjacent fins. a

The invention also resides in the novel construction of the grille which permits the forma-- tion of deflecting or diflusing elements along edge portions of the grille fins.

Another object is to provide a novel method of forminga grille of the above character from sheet of metal.

Other objects and advantages of invention will become apparent from the following detailed description taken in connection with the accompanying drawings, in which Figure 1 is a front elevational view of a grille embodying the present invention.

Fig. 2 is a fragmentary sectional view taken along theline 2--2 of Fig. 1.

Fig. 3 is a fragmentary perspective view of the improved grille core in the process of construction.

Fig. 4 is a cross sectional view taken through the core shown in Fig. 3 and the cooperating die members by which the core is formed.

Figs. 5 and 6 are fragmentary views of a portion of Fig. 4 illustrating different steps in the folding process. I

While the invention is susceptible of .v'arious modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preferred embodimennbut it is to be understood that I. do not thereby intend to limit the invention to the specific form or method disclosed, but intend to cover all modifications and alternative constructions and methods falling within the spirit and scope of the invention as expressed in the appended claims.

The grille shown in the drawings for purposes 'of illustration is of the type generally used for covering the discharge outletsin air distributing systems and comprises a core 1. mounted in a frame 8 adapted to be supported in the open end of an air duct 9. The core comprises a plurality oi thin fins I! supported in spaced parallel planes and disposed edgewise to the direction of air fiow from the duct, each fin comprising in the present instance a single thickness of thin sheet metal.

If the grille is to be used for imparting directional control to the air stream discharged from the grille face, the fins are made'substantially wider than the spaces between them. Parallel relation of the fins is maintained by spacing or connecting elements ll spaced longitudinally of the fins and each integrally joined at its opposite ends to the adjacent fins. Herein, the elements [I are substantially straight intermediatetheirends and extend generally diagonally of the space between the adjacent fins with their opposite ends rounded slightly at the points of mergence with the fins. A substantially rigid connection is thus formed between the front side edge of one. fin and the rear edge of the adjacent fin.

It will be observed that the spaced parallel fins define between them narrow air passages for the fiow of air through the grille, the opposing faces of the fins constituting parallel walls which are continuous throughout the length of the fins. The connecting elements extend diagonally across the air passages thus formed at longitudinally spaced points, and since'their only function is that of maintaining the fins in properly spaced relation, they are spaced a substantial distance apart and made as narrow as possible consistent with the performance of this function, thereby reducing the resistance interposed by the connecting elements to the fiow of air through the grille. Thus, the length of the air passages longitudinally of the fins is a multiple-of, that is, several times, the

width of the connecting element and the latter width isa small fraction of the distance between the adjacent elements connecting adjacent fins.

In the present ins'tance, spaced deflecting ordiffusing elements II are positioned along the edge portionsof the grille fins and comprise short projections depressed in .or'bent from the edge portions of the fins without severing the metal at such edges. of course, these projections may be in various shapes according to the desired inclination and eflective area of the deflecting surfaces defined by the projections. By forming the projections along one side edge only of the fins,

35 of the width of an individual connecting element.

. advance.

presenting the same general appearance when viewed from either side of the grille.

By deforming the individual fins to form the projections i 2 and utilizing the diagonal connecting elements il spaced relatively close together along the fins, a truss-like structure is provided which possesses a substantial degree of rigidity as is desired in grilles of the present character.

The grille above described lends itself to manufacture at low cost by a novel method of punching and folding a single'sheet ll of thin metal. As illustrated herein, the method comprises punching parallel rows of elongated apertures 16 in the sheet to leave strips l6 of metal intervening between the adjacent rows and having parallel side edges, deforming the edge portions of the strips I6 to form the projections l2, and finally, while maintaining each strip infiattened condition, folding or corrugating the perforated and deformed sheet by relatively-bending the crosspieces l1 and the strips it along lines substantially coincident with the side edges of the strips so as 'to bring the strips i6 into parallelism throughout their lengths and widths with the cross pieces I! of metal intervening. between the adjacent apertures of each row connectingthe adjacent strips. The rows of apertures l6 are spaced apart so that the strips l6 which when bent into parallel rela-. tion constitute the fins Ill in the finished grille will be of the desired width. Similarly, the width of the apertures is proportioned according to the desired spacing of the fins in the complete grille. The lengths of the apertures 16 determine the lateral spacing of the connecting elements Ii in the finished grille and each length is a multiple Referring now to Figs. 4 and 5, the steps in the method above described are preferably performed upon the metal sheet as it is advanced step-bystep through sets of dies arranged in spaced relation. In the embodiment shown, the apertures I6 are punched by cooperating male and female dies l8 and I! which operate while the sheet is being held in proper position by suitable locating punches 20, which are projected through previ- A die having properly While the diesl6 and 22 are retracted, the perforated sheet is held raised above the dies 2| by a block 23 normally urged upwardly to the position shown in Fig. 4 thereby permitting the sheet to Folding of the perforated sheet so that each strip l6 forms'a fin i0 is preferably efiected in two stages, the first occurring in the initial downward movement of a projection 24 on a vertically movable block 25 into the space between the block 23 and an upstanding but downwardly retractible projection 26. In such movement, the preceding fold is held against retraction by a projection movable downwardly with the projection 26 so that the portion of the sheet between the projection 26 and the block 23'isbent downwardly as illustrated in Fig. 5, the unbent portion of the sheet being advanced along the block 23 to permit The die block 25 is mounted to slide horizontally on its support and in the continued downward movement of the latter, a cam surface 3| on the block 26 cooperates with a stationary cam 22 to of the proper size through the dies.

shift the projection 24 toward the vertical wall of the projection 26 thereby bringing the engaged strip i6 into parallelism with the previously formed fins as shown in Fig. 6. Final shaping of the connecting element i I engaged by the inclined surface of the projection 24 occurs in the next stroke of the dies when this element is pressed between the inclined surfaces of the projections 26 and 26 and the fin is straightened between the vertical surface of the projection" and the opposed surface of an upstanding projection 21 paralleling the projection 26. In the final movement of the forming dies to the positions shown in Fig. 6, the locating-pins 20 engage the strip after which the perforatin punches I6 operate. Then, after retraction of t e dies I8, 20, 22, 24 and 26, the'metal sheet is raised by the block 23 and the projections 26 and 21 are retracted to permit the sheet to be advanced for the next cycle.

With the method above described, grilles composed of any number of fins and having any selected length less than the width of the dies may be constructed simply by passing a sheet of metal Thus, the present invention enables grille cores of widely varying sizes to be constructed quickly and atalow cost comparable to perforated plate grilles. In addition, the present grille is characterized by a large free air area and an artistic frontal appearance more nearly comparable to the more expensive fabricated sheet metal grilles now in common use. The fins may be made of any desired width relative to the spacing therebetween degree or obtaining directional control of the I discharged air stream. Also, by varying the shape of the coacting folding dies, the fins i0 may be disposed relative to the face of the grille at any angle other than the right angle shown.

I claim as my invention:

1. A grille through which air' is to be blown,

having a core made from a single sheet of metal and comprising a multiplicityof thin parallel fins each comprising a single layer of metal, said fins beingspaced apart to define between them narrow air passages having opposed parallel walls continuous throughout the length of the fins, and narrow connecting elements integrally joined at opposite ends to opposite side edges of adjacent fins and extending diagonally across said passages at points spaced apart longitudinally of the passages, the length of the individual air passages between adjacent connecting elements being a multiple of the width of each connecting element so thatsaid elements, while maintaining the spacing of said fins, offer comparatively small resistance to thefiow of air through the grille.

2. A grille through which air is to be blown,-

allel to each other throughout the length and width of the fins, and narrow connecting elements integrally joined at opposite ends to opposite side edges of adjacent fins and extending diagonally across said passages at points spaced apart longitudinally of the passages, the length of the individual air passages between adjacent connecting elements being a multiple of the width of each maintaining the spacing of said fins, oil'er comconnecting element so that said elements, while paratively small resistance tolthe fiow 3..ihcmethodoi'tormingariarallelfingrille irom a sheet of metal which comprises first punching out metal from said sheetto iorm parallel rows oi apertures with the adjacent rows separated by continuous metal strips each havingparallel side edges and a width equal to that of one grille fin to be formed, the length of each aperture measured longitudinally of its row being armors Y 0! air whiiemaintainingthestripsmbstantially fiat and the edges thereof deformed.

4. The method oi forming a parallel fin grille from a sheet of metal which comprises first punching out metal irom said sheet to form apertures arranged end toend in spaced parallel rows with the adjacent rows separated by continuous metal strips having parallel side edges and integrally joined by narrow connecting elements separatingthe adjacent apertures in the individual rows, each element having a width which is a small fraction 01' the length of an individual aperture, and relatively bending said strips and connecting elements along lines substantially coincident with the longitudinal side edges of said strips to bring said strips into parallelism throughout their lengths and widths and to extend said elements diagonally of the spaces between the adjacent strips.

. GEORQE DRAKE. 20 

